A Cupful of Compass
By R.E. Matthews ~ Illustrated by Anni Matsick
Here’s an easy way to make a magnetic compass. The only things you need that may not be in your kitchen are a magnet and a large sewing needle.
Make the sewing needle into a magnet: lay one end of the needle against one end of the magnet and slowly pull the needle away, making the needle slide against the magnet. Do this five or six times.
Make sure the needle works like a magnet. It should move toward anything that the magnet attracts, such as a metal fork.
If the needle does not work like a magnet, draw it across the magnet several more times in the same way as before. If it still doesn’t work, you may need to draw it across a stronger magnet.
Cut a square of waxed paper that will fit easily into a cup or bowl. Fold the square of paper diagonally, and carefully stick the needle through the paper at the center of the fold, like the image at right.
Now flatten out the paper square and let it float in a cup or bowl of water. The paper square should float and turn freely. If it does, you will see that it turns slowly until the needle points in a special direction. Even if you move it with your finger, it will turn back to that same direction.
The compass works because the earth is a big magnet that is lined up north and south. The magnetic forces of the earth’s big magnet pull and push on the magnetic needle until it also lines up north and south.
There is one more step in making a compass. You need to know which end of the needle points north and which end points south. You may already know which way is north. If you don’t, here’s how to find out. Notice where the sun rises and sets. It rises in the general direction of the east and sets in the west. Stand with “sunrise” on your right and “sunset” on your left, and you will be facing north with south behind you.
Now you can tell which end of the needle is pointing north. Take your waxed-paper square and needle out of the cup. Put N on the north corner. Put an S for south on the opposite corner. Mark the corner to the right of north E for east, where the sun rises in the morning. Mark the corner to the left of north W for west, where the sun sets every evening.
Now you have two different ways to find the directions, north, east, south, and west—a compass and the sun.
- Some things will fool your compass if they get close enough. Try holding your magnet above the compass and turning the magnet around. If a magnet gets close enough to your compass, its effect is stronger than that of the earth’s magnet. Anything made of iron will also fool your compass if it gets close enough because the magnetized needle will be attracted to the iron.
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